package Test;

class s{
    int a;
    int b;
    public s(){
    }
    public s(int a,int b){
        this.a=a;
        this.b=b;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof s s)) return false;
        return a == s.a && b == s.b;
    }
    
}

public class XX {
    public static void main(String[] args) {

        s ss=new s(1,2);
        s ss1=new s(1,2);
        System.out.println(ss==ss1);
        System.out.println(ss.equals(ss1));
        StringBuilder s=new StringBuilder("g");

        StringBuilder f=new StringBuilder("g");
        System.out.println(s==f);
        System.out.println("aa"=="aa");
    }
}
